Chapter 8.4, Problem 6P

Following Euclid’s proof that there are infinitely many primes, and starting the list with 5 and 7, you form the number $5\times 7+1=36,$ and you get the new prime numbers 2 and 3 because $36=2\times 2\times 3\times 3.$ Which new prime numbers would you get if your starting list were the following?

a. 2, 3, 5

b. 2, 3, 5, 7

c. 3, 5